As a piece of entertainment, Hail, Caesar! performs the function a night at the movies once did, providing a little bit of song and dance, a little bit of mystery, and a little bit of sex.

Undoubtedly the strongest influence on the comedies of Joel and Ethan Coen is the great Preston Sturges. Having borrowed the title of O Brother Where Art Thou? from Sullivan's Travels, the brothers now lift that movie's theme for Hail, Caesar, which, as with Sturges' film, argues the case that the best way actors can help the world is to stick with what they do best - entertaining. But where Sullivan's nail its colours firmly to this particular mast, the Coens' film leaves us unsure as to whether its an endorsement or a cynical condemnation of this view.

Josh Brolin plays a fictionalised version of Eddie Mannix, the MGM studio exec who acted as a Michael Clayton style 'fixer', helping out the studio's stars when they found themselves in compromising positions. Here Mannix works for the fictional Capital Pictures, overseeing a roster of troublesome stars. There's Baird Whitlock (George Clooney), a Victor Mature-alike star of sword and sandal epics, who finds himself kidnapped and held for ransom by a group of communist screenwriters; there's DeeAnna Moran (Scarlett Johansson), an aquatic performer in the Esther Williams mould, who's gotten herself pregnant out of wedlock, a no-no in '50s Hollywood; and there's singing cowboy Hobie Doyle (Alden Ehrenreich), who finds himself transferred from his comfort zone of B-westerns to a talky melodrama, much to the annoyance of director Laurence Laurenz (Ralph Fiennes). Sniffing around Mannix for stories and scandals are a pair of Hedda Hopper-esque twin gossip columnists played by Tilda Swinton.While following Mannix as he navigates his studio we witness a series of set-pieces from fictional Capital Pictures productions. Hobie Doyle performs over the top stunts while fighting bandits; DeeAnna Moran and a troupe of aquatic starlets dazzle in a display of synchronised swimming; and in the film's standout sequence, Channing Tatum gets a chance to display his dancing skills in 'No Dames', an Anchors Aweigh type dance number featuring a particularly camp group of sailors.

With Clooney as a dumb actor who falls for the first political movement he's exposed to, the Coens seem to be poking fun at the real life persona of Clooney and the many stars who appear to take up random causes at some point in their careers. Mannix has no time for any of this do-gooder nonsense; to him it's all about the picture. You get the impression here that the Coens may agree with Hitchcock's statement that actors should be treated like cattle; Mannix spends his day chasing actors like a rancher chasing bulls, and when Hobie is asked how he entered the movie business, he claims to have been 'roped in' to Hollywood. Speaking of Hitch, the film is packed with Easter Eggs for fans of the master of suspense, from an actress named Carlotta Valdez, to a secretary whose appearance is borrowed from Jane Wyman's Stage Fright heroine, to the appearance of Shadow of a Doubt's theme tune over the credits of one of Capital Pictures' productions.For fans of classic Hollywood, Hail, Caesar! is something of a double edged sword. The movie is a love letter to the era, but it seems to have been written with a poison pen, its loving homages veering a little too close to cheap jibes. None of the movie recreations really resemble those found in '50s spectacles; they're closer to the sort of sequences you might find in an episode of The Muppet Show. In fact, structurally, Hail, Caesar! feels a lot like a live action Muppet movie, employing the hook of a central crime as a paper-thin plot on which to hang a series of musical numbers and comic set-pieces. Will the Coens encourage viewers to explore classic Hollywood? I'm not sure. I worry many younger viewers may take the homages here at face value and dismiss mid 20th century cinema as a series of laughably innocent clichés.

If you're looking for the depth of an Inside Llewyn Davis, you'll struggle to find much beyond the central theme lifted from Sturges, but as a piece of entertainment, Hail, Caesar! performs the function a night at the movies once did, providing a little bit of song and dance, a little bit of mystery, and a little bit of sex.